This invention relates to pillows, and specifically to pillows which are designed to provide proper alignment of the spine.
Pillows have existed for centuries. Typically, a pillow consists of an envelope filled with a soft material, such as down, spun fibers, foam rubber, and the like. While these pillows provide comfort during sleep they also orient the head of person so as to misalign the head with the spine. This misalignment may result in physical problems to the human body.
Recently, pillows have been designed having a top surface contoured in a manner to better align the head and spine during sleep. These pillows however are typically designed with atop surface having one fixed shape. As such, these pillows do not properly conform to all users having different neck lengths, head sizes or other physical differences between individuals.
Contourable pillows have also been designed having an air impermeable outer envelope, an air permeable interior material, and a control valve coupled to the outer envelope which controls the release of air within the outer envelope to ambience, as shown in U.S. Pat. No. 3,864,766. With the application of pressure upon the pillow and the opening of the control valve the interior material compresses in the area of the pressure, thereby forcing the air from that portion of the interior material. With the closing of the valve the interior material is intended to maintain the depressed, air voided area so as to maintain that depressed contour. Realistically however the contour is not maintained since air migrates from the undepressed portion of the interior material to the depressed portion as the user""s head moves from one portion of the pillow to another.
Contourable pillows have also been designed wherein opposite sides of the exterior envelope may be secured in different areas to provide a contour, as shown in U.S. Pat. No. 5,363,524. The user of these pillows must estimate the desired contour and then configure that desired contour by manually manipulating the interior material. As such, the pillow still may not provide the correct contour for proper alignment of the head and spine.
Contourable pillows have also been provided having multiple, parallel chambers in fluid communication with each other, as shown in U.S. Pat. Nos. 5,642,544 and 5,898,963. Here, fluid may pass from one chamber to another through an opening extending through a common wall of the chambers. As the fluid may flow back and forth from one chamber to another the contour of the pillow is not maintained as different pressures are applied to different areas of the pillow.
Accordingly, it is seen that a need remains for a contourable pillow which may maintain a configuration adapted for a particular individual even though subsequent movement of the user""s head may occur. It is to the provision of such therefore that the present invention is primarily directed.
In a preferred form of the invention an orthotic pillow comprises a central compartment adapted to hold a fluid, a peripheral compartment adapted to hold a fluid which substantially surrounds the central compartment, and an unidirectional control valve coupled to the central compartment which allows the flow of fluids from the central compartment to the peripheral compartment. With this construction, as the head of a person is placed upon the pillow""s central compartment fluid within the central compartment is pressurized causing the fluid to pass through the control valve into the peripheral compartment so as to relieve the pressure upon the head and increase the pressure upon the neck so as to induce proper alignment of the neck during sleep.